Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e79b86ed2b9ae44…

MALICIOUS

PDF

87.8 KB Created: 2021-06-26 09:04:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: a761e603dd1e297ec9a8ac66fdbeb8b2 SHA-1: 546db2f9a7ab6d4922658baa3d14591132f80f9d SHA-256: 8e79b86ed2b9ae44b4b22090e9f229ad6d7e0c6834faa221c321aa8f73648ffa
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external resources, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document, potentially leveraging embedded JavaScript for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://freeski.hu/freeski/file/nizofawunuwezelalusixet.pdf In PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/5c109d14c3f9d1123debfe225476e253/14860322896.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/tvgpbtekghi79ghmtu871hhih2/61274017105.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c6f85111b2e---16934071870.pdfIn PDF document text
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/7b5b25f7d101e1382e193caec542e6a0/67915295712.pdfIn PDF document text
    • http://weifong.tw/fckimages/file/9237670049.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb673b0678---27170858301.pdfIn PDF document text
    • https://hpsoft.shop/upload/files/somegelasuvepaf.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f07fa6cac3---defigaxewarufe.pdfIn PDF document text
    • http://chataphan.com/file_media/file_image/file/wisibomewim.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160779548591da---65941709841.pdfIn PDF document text
    • http://triatlonbizuterie.cz/sites/default/files/file/29261344137.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1606f11df9aebb---3536137975.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ee9777d1bd---zarozagudu.pdfIn PDF document text
    • http://vintageguitar.ru/ckfinder/userfiles/files/51774812815.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609642e7f127e---76126417787.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/oam1od2cm1bo3b8631lfbst5dn/14345961243.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/q1c0ugdrta2m694pul7i6e9491/medogometetokukuvet.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607e4172603fc---8031778593.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ad9b1f43516---sopinir.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096fd5da64f8---gijupi.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/8s5rvvbb8lopv9oop629uodia5/97081395255.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4ae8f56c31---56390526049.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=does+alcohol+help+benzo+withdrawal+redditPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f680.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF680 16296 bytes
SHA-256: a4989c61aa3739747caf7d92049c90ea793cc081d480e2fd16d82f2b1f45fbc7
font_01_sfnt_off000120a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120A8 10896 bytes
SHA-256: f36eda1b19352abef63360422e2d49e3ccb0cf95a6b95bbe26d82235c1c0553a
font_02_sfnt_off000139b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139B5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1